1. Field of the Invention
This invention relates generally to an adaptive climate control system and, more particularly, to a climate control system for controlling the climate within the passenger compartment of a vehicle where manual adjustments to the climate control system by a vehicle operator are processed to adapt the climate control system to the comfort level of the operator.
2. Discussion of the Related Art
As is well understood, a number of controls, such as blower speed control, temperature control and vent control, that control a heating ventilating and air conditioning (HVAC) system associated with a vehicle enable a vehicle operator to regulate the climate within the vehicle. FIG. 1 shows a diagrammatic view of a typical control panel 10 for such an HVAC system. The control panel 10 includes a display 12 that displays a temperature setting, generally based on the Fahrenheit temperature scale. The temperature setting represents a scaled value that allows the HVAC system to deliver an air mixture to the passenger compartment of the vehicle at a particular temperature. A temperature set control button 14 enables the vehicle operator to adjust the temperature setting in order to raise or lower the temperature over a predetermined temperature range. A blower speed control button 16 allows the vehicle operator to change the speed of a blower that delivers the air mixture at the desired temperature to the blower vents so as to adjust the rate at which the air mixture is delivered to the passenger compartment of the vehicle. The blower speed may also be shown within the display 12. Vent control buttons 18, shown here as upper, bi-level, lower, and defog controls, allows the vehicle operator to determine which vents will deliver the air mixture at the set blower speed. Front and rear control buttons 20 allow the vehicle operator to select front and rear defrost. An air conditioning (A/C) control button 22 allows the vehicle operator to select air conditioning for cooling. A recirculation control button 24 recirculates the vehicle compartment air during extreme climate conditions. A pass button 26 allows a vehicle passenger to switch control of the HVAC system to a passenger control panel. Each of the above-discussed controls are well known controls of a vehicle climate control system.
Advancements in HVAC systems for controlling the climate within a vehicle have lead to electronic climate control (ECC) systems that will automatically control the climate within the passenger compartment of the vehicle based on a number of parameters that effect the climate within the vehicle. The parameters are preprogrammed and calibrated to a particular comfort level by a climate control calibration engineer at the manufacturing level of the vehicle. An automatic control button allows the vehicle user to put the ECC system into the automatic mode. For the control panel 10, the automatic mode can be selected by pressing the temperature set button 14. In the automatic mode, the ECC system will attempt to regulate air delivery and air mixture based on the preprogrammed parameters. If the vehicle operator adjusts the blower speed, or any other control button on the control panel 110 besides the temperature set control button 14, the ECC system will be removed from the automatic mode, and will remain at the settings as set by the vehicle operator. The goal of an automatic ECC system is to provide the most desirable comfort level within the vehicle compartment with a minimal amount of control input by the vehicle operator.
One automatic ECC system, developed by Delco Electronics, uses the ambient air temperature outside of the vehicle (T.sub.out), the temperature within the vehicle compartment converted to digital counts (T.sub.IN), the solar load (T.sub.SL) on the vehicle, the temperature setting that is set by the vehicle operator (T.sub.SET), and a calibration constant (K) as the parameters for determining the automatic climate control. The ambient air temperature T.sub.out is sensed by a temperature sensor that provides a voltage representation of T.sub.OUT. The voltage is applied to an ambient air corrections (ACOR) table that provides an indicative ambient temperature corrections factor F.sub.ACOR based on the ambient air temperature T.sub.OUT. For this system, the ACOR table includes thirty-two data points for representing the entire range of the sensed ambient air temperatures. The ACOR values are determined by interpolating the voltage representation of the ambient air temperature across the ACOR table data points. Therefore, each ACOR table value represents a range of temperatures.
An algorithm has been devised for controlling a single zone automatic ECC system that correlates these parameters into one control variable program number (NPRG). This algorithm is given by: EQU NPRG=2T.sub.IN +5T.sub.SET +F.sub.ACOR +T.sub.SL +K.
The NPRG value is the value by which the automatic ECC system determines the appropriate blower speed, vent mode and air mixture in order to set the climate within the vehicle. The calculation for the NPRG value can also include a compensation for other zones. In the system described above, the NPRG value can be between 0 and 256 based on an eight bit digital data byte. A high NPRG value indicates that the ambient air temperature and the vehicle compartment air temperature are relatively cold, and therefore heat should be delivered at a high blower speed. Likewise, a low NPRG value indicates that the ambient air temperature and the vehicle compartment air temperature are relatively high, and therefore cool air should be delivered at a high blower speed. Each NPRG value allows the automatic ECC system to know to provide a certain air mixture at a certain blower speed to achieve the value of T.sub.SET.
As mentioned above, the NPRG value will cause the system to select which of the blower outlet vents will receive what proportion of the blower capacity, and the particular blower speed for the environmental conditions. When the automatic ECC system calculates a NPRG value, it will then refer to a blower look-up table in order to determine the appropriate blower speed. Like the ACOR table, the blower look-up table has thirty-two data points. The NPRG value is interpolated across the blower look-up table such that each data point in the blower look-up table represents a range of NPRG values. Therefore, for example, if a vehicle operator enters the vehicle on a hot day, the automatic ECC system will provide the quickest way of achieving the temperature set point by providing the best possible air temperature mixture, blower speed and blower vent mode.
The automatic ECC system discussed above is intended to automatically provide the most desirable vehicle climate for the vehicle operator. In order to set the controls that determine the appropriate air mixture, blower speed and blower vent mode for a particular NPRG value for a wide-range of environmental conditions, a calibration engineer sets the blower speed and the air mixture for each NPRG value based on his preference or the preference of a minimal cross section of people. The calibration constant K enables the calibration engineer to insert a parameter into the calculation of the NPRG value that adjusts the NPRG value for each combination of T.sub.IN, T.sub.OUT, T.sub.SET and T.sub.SL based on the engineer's preferences.
An inherent problem exists in the above described system. That is, the vehicle operator may desire a different vehicle compartment temperature than that as calibrated by the calibration engineer at a particular T.sub.SET value with respect to the other parameters. Further, known automatic ECC system do not account for sensitivity to blower noise. High blower speeds may provide annoying circumstances to certain individuals. Therefore, some vehicle operators may consistently adjust the climate controls, thus removing the system from the automatic mode. These operators will therefore not benefit from the automatic climate control system.
What is needed is an adaptive climate control system that allows the automatic ECC system to be calibrated to a particular vehicle operator so that the automatic ECC system will be specifically adaptable to that particular vehicle operator, and thus minimize vehicle operator control changes to the climate control system. It is therefore an object of the present invention to provide such an adaptive climate control system.